Conversion to Ebike

Pop

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I am new to the Forum, new to Ebiking and pretty incompetent when it comes to technical things.
I want to convert my Specialized Roll Sport Step Through to electric. Based on my research and budget I think I am settled on the Bafang BBS02B 48V 500W kit.
I was thinking the 44T gearing and a 48V 12 ah battery
Can anyone identify serious flaws in this configuration or offer suggestions on the best approach to the project?
Thanks for any help offered.
 
@Browneye converted his wife's Specialized Roll to electric last week. You'll find pictures of the bike and a short video in this thread.

He went with a rear-hub conversion but also looked at mid-drives.
 
If you are able to afford it go with a 48v x 17ah battery unless you like to pedal a lot, myself i`m very lazy and prefer the bike do it for me as much as possible and for as long as the battery lasts (hence the 17ah vs 12ah). Everyone has their preference on how to make it work best for their situation. Best of luck on your build and don`t forget to show the end result with lots of pictures.
 
I did the BBS02 on a beater DIamondback hybrid in 2016. It's a very quiet motor, more than enough power for me. I've had it on the rail-trails in Colorado.

Comparatively speaking, a BBS02 install is fairly easy, compared to a hub motor.

You will need a crank arm puller ($10-15) to remove the pedal arms. You might need another tool ($10-15) to remove the axle. Take it to a bike shop, and I bet they can remove both for less than the price of the tools. There is a special wrench that is useful for tightening the BBS02 to the frame. Sometimes included in the kit. Buy it, if it is offered.

Edit. You might need a chainbreaker tool ($8) to get the chain off the front derailleur, as that is no longer used. Then you have to buy a $5 link to put it back together.

The wiring on a BBS02 is easy. You'll find how-to-do-its on you tube. If you're not electrically inclined, the connection between the battery and motor will be your only challenge. Worst case, you can crimp it.

Battery consumption is directly related to speed. I've done over 45 miles on a 12AH battery, but that's going at an easy 14 mph. Pushing 18 mph, or in cold weather, I would derate mine to 30 miles.
 
pretty incompetent when it comes to technical things This line gives me pause. Maybe you can't handle tech, but you are a great bike mechanic?
 
Not that either but a v ery tech savvy and mechanically competent friend is on board to help with the conversion.
 
Did 15 mi yesterday and 22 today, and both bikes used less than 40% of their capacity, and effortless . We’re pretty stoked.

Roll with 500w 48v geared hub, 11ah batt.
Giant Explore Yamaha middrive 250w 36v 11ah.

Very happy with range on both- they are very similar.

We averaged about 12mph overall.
More speed takes more juice.
 
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Best just go with the 750W. 500W replacement controller and rotors are likely not as easy to find. BBS02 motors need to be ridden like a typical bike. Using the range of gears. For a more forgiving motor consider a BBSHD.
 
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Did 15 mi yesterday and 22 today, and both bikes used less than 40% of their capacity, and effortless . We’re pretty stoked.

Roll with 500w 48v geared hub, 11ah batt.
Giant Explore Yamaha middrive 250w 36v 11ah.

Very happy with range on both- they are very similar.

We averaged about 12mph overall.
More speed takes more juice.
I notice your wife's Roll has the slick tires mine does. Do you ride on any loose terrain or mostly pavement? Wondering how they might handle.
 
I notice your wife's Roll has the slick tires mine does. Do you ride on any loose terrain or mostly pavement? Wondering how they might handle.

We are 99% on pavement. But the few patches of decomposed granite or hardpak, they work fine too.
They're cushy, but for a pedal bike some extra drag. For the ebike conversion they're ideal. In fact I'm tempted to put something similar on my 700c wheels on mine. I test rode some ebike mtb's with huge tires on them and they were no problem on tarmac.
 
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